The present invention relates to a drive mechanism for the steering wheels of a vehicle and, more particularly, to an all wheel drive for an agricultural tractor with front wheel steering.
For several years, it has generally been recognized that all wheel drive for agricultural tractors with front wheel steering has many advantages over conventional two wheel drive tractors. For instance, all wheel drive gives up to 50% better traction and 25 to 30% more pulling power to keep the tractor moving on all kinds of soil and, as a result, it is possible to get more done in less time and to avoid losing time because of soil conditions since it is possible to plow even when the soil is wet. Moreover, because of the increased traction and added pulling power, all wheel drive provides significant savings in increased fuel efficiency, reduced tire wear, and extended tractor life.
Because of the advantages in all wheel drive, conversions are available for conventional two wheel drive tractors. Among the best conversions available are those manufactured and sold by Elwood Manufacturing Company of Elwood, Ill. which are simple to maintain, easy to install, provide good maneuverability with a 35.degree. steer on 30 inch rows, result in less soil compaction because the power on the front wheels eliminates the necessity to load the rear of the tractor with ballast, provide 12.degree. oscillation so all four wheels maintain ground contact all of the time, and give sufficient mid tractor ground clearance to run the tractor over the roughest terrain without damaging the drive line. Despite these advantages, it has remained to provide an all wheel drive conversion with adjustable tread width having a significantly reduced turning radius.
It is therefore an object of the present invention to provide a drive mechanism for the steering wheels of a vehicle which takes full advantage of the many features inherent in prior devices while overcoming the few remaining obstacles to perfecting the design, construction and operation of such devices.
These and other objects, features and advantages of the present invention will become apparent from the following description when considered in connection with the accompanying drawings.